Original by LemonLake (Drew Lemmy).
https://bitbucket.org/Lemmmy/factory/

Forum link:
https://forum.minetest.net/viewtopic.php?f=11&t=9277

Forked on github to bring it back to a working state.

Original readme.txt said:

Change this folder name from 'LemonLake-factory-xxxxxx' to 'factory' or else it won't work!